My CD player in my base radio is jammed and the paint is chipping off one of the memory buttons, so I think it's time to replace the radio. Should I go with aftermarket or just get a stock one from the Web? Would I be able to get the one with the navigation and touch screen (i.e. is it the same connector as the base radio?)

 

Welcome to the forum.
I doubt the connectors match between the base radio and the nav radio. Personally I would steer away from the GM nav radio because their early systems were rather sketchy. I think you'd find a Garmin to be a better alternative if you need an nav system. You could check with Crutchfield to see what aftermarket radios are available and they can also provide connector adapter harnesses.

 

Base radio and NAV radio are compatible. Each directly plugs in. If you buy a NAV radio it has to be programmed to work with your car. You also need an anteena and USB cable.

 

Since this thread is at least 7 years old, the probability is high that he is no longer interested and may not even own the car anymore.